5. Move the grub.efi to overwrite the archiso supplied one (which btw works on my desktop. I guess GRUB includes more workarounds for buggy firmware from manufactureres. See this video, if you have time: http://mjg59.dreamwidth.org/10014.html

Wireless

Touchscreen

Works out of the box.
Haven't looked for possibilities to configure multi-touch.

Video

The video card installed is Intel HD Graphics 4000. See intel for more info.

Install the video driver with pacman -S xf86-video-intel

Brightness control

Default brightness adjustment keys work but need to be pressed multiple times to increase/decrease the screen brightness. Writing your own acpi handlers for those buttons seems to have no effect. In order to use it properly you need to append a new kernel parameter and make new grub config. Make sure to escape double quotes.

KMS

Webcam

Works out of the box. Tested with guvcview

Fingerprint Reader

fingerprint-guiAUR from the AUR is already patched to work with the X1's newer fingerprint reader. To get the gui's dropdown to recognize your device, you'll have to add your user to the plugdev group: